title: Brefeldin A affects synthesis and integrity of a eukaryotic flagellum.
abstract: Eukaryotic flagella and cilia are highly dynamic organelles. In green algae like Chlamydomonas reinhardtii, flagella absorption and resynthesis is a normal process during the vegetative cell cycle. Rapid regeneration also occurs after stress-induced shedding of flagella. Ca2+ ions, protein synthesis, and a kinase activity are the main factors known to affect resynthesis. Recently, we have detected that certain small G proteins (Ypt/Rab) and a GTPase regulator (GDP dissociation inhibitor), known as regulatory elements of intracellular vesicle transport, are present in flagellar membranes of green algae, raising the possibility that the organelle's synthesis and/or integrity depends on functional membrane traffic. In this study, we examined the effect of brefeldin A (BFA), an inhibitor of intracellular membrane flow and Golgi function in animal and plant cells, on flagella regeneration in the colonial green alga Gonium pectorale. We show that low BFA concentrations (< 1 microgram/ml) inhibit flagella out-growth, while higher amounts cause dose-dependent deflagellation and cell death. Our findings provide experimental evidence for a direct connection between intracellular transport and eukaryotic flagella synthesis.
authors.affiliation: Institut für Biochemie, Genetik und Mikrobiologie, Universität Regensburg, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Haller
authors.forename: S
authors.initials: S
authors.lastname: Fabry
mesh_terms: D020126:Brefeldin A; D003517:Cyclopentanes / Q000494:pharmacology*; D056890:Eukaryota / Q000187:drug effects*; D005407:Flagella / Q000187:drug effects*; D006056:Golgi Apparatus / Q000187:drug effects; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D012038:Regeneration / Q000187:drug effects / Q000502:physiology
chemical_list: D003517:Cyclopentanes; D011500:Protein Synthesis Inhibitors; D020126:Brefeldin A